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1.
Background
The induction of metalloprotease encoded by empA in Vibrio anguillarum occurs at high cell density in salmon intestinal mucus. Previously we have shown that there are significant differences in empA expression in two strains of V. anguillarum, M93Sm and NB10. It is hypothesized that differences in empA regulation are due to differences in binding of regulatory elements. 相似文献2.
Anna Pistocchi Germano Gaudenzi Silvia Carra Erica Bresciani Luca Del Giacco Franco Cotelli 《BMC developmental biology》2008,8(1):27
Background
Prox1, the vertebrate homolog of prospero in Drosophila melanogaster, is a divergent homeogene that regulates cell proliferation, fate determination and differentiation during vertebrate embryonic development. 相似文献3.
Aims
To test the hypothesis that Mycobacterium bovis can persist in the environment within protozoa.Methods and Results
In this study, we used a novel approach to detect internalized mycobacteria in environmental protozoa from badger latrines. Acid‐fast micro‐organisms were visualized in isolated amoebae, although we were unable to identify them to species level as no mycobacteria were grown from these samples nor was M. bovis detected by IS6110 PCR. Co‐incubation of Acanthamoeba castellanii with virulent M. bovis substantially reduced levels of bacilli, indicating that the amoebae have a negative effect on the persistence of M. bovis.Conclusions
The internalization of mycobacteria in protozoa might be a rare event under environmental conditions. The results suggest that amoebae might contribute to the inactivation of M. bovis rather than representing a potential environmental reservoir.Significance and Impact of the Study
Protozoa have been suggested to act as an environmental reservoir for M. bovis. The current study suggests that environmental amoebae play at most a minor role as potential reservoirs of M. bovis and that protozoa might inhibit persistence of M. bovis in the environment. 相似文献4.
5.
Background
Of the major families of long terminal repeat (LTR) retrotransposons, the Pao/BEL family is probably the least well studied. It is becoming apparent that numerous LTR retrotransposons and other mobile genetic elements have colonized the genome of the human blood fluke, Schistosoma mansoni. 相似文献6.
Elaine M Forbes Siân R Nieduszynska Fiona K Brunton Joanne Gibson L Anne Glover Ian Stansfield 《BMC molecular biology》2007,8(1):94
Background
In the C. albicans retrotransposon Tca2, the gag and pol ORFs are separated by a UGA stop codon, 3' of which is a potential RNA pseudoknot. It is unclear how the Tca2 gag UGA codon is bypassed to allow pol expression. However, in other retroelements, translational readthrough of the gag stop codon can be directed by its flanking sequence, including a 3' pseudoknot. 相似文献7.
Alex L Pereira Thiago N Silva Ana CMM Gomes Ana CG Araújo Loreny G Giugliano 《BMC microbiology》2010,10(1):57
Background
Enteroaggregative Escherichia coli (EAEC) are enteropathogenic strains identified by the aggregative adhesion (AA) pattern that share the capability to form biofilms. Citrobacter freundii is classically considered as an indigenous intestinal species that is sporadically associated with diarrhea. 相似文献8.
Aya Fukui-Miyazaki Shigeki Kamitani Masami Miyake Yasuhiko Horiguchi 《BMC microbiology》2010,10(1):247
Background
Bordetella dermonecrotic toxin (DNT) causes the turbinate atrophy in swine atrophic rhinitis, caused by a Bordetella bronchiseptica infection of pigs, by inhibiting osteoblastic differentiation. The toxin is not actively secreted from the bacteria, and is presumed to be present in only small amounts in infected areas. How such small amounts can affect target tissues is unknown. 相似文献9.
Peter Sass Andrea Jansen Christiane Szekat Vera Sass Hans-Georg Sahl Gabriele Bierbaum 《BMC microbiology》2008,8(1):186
Background
The lantibiotic mersacidin is an antimicrobial peptide of 20 amino acids that is ribosomally produced by Bacillus sp. strain HIL Y-85,54728. Mersacidin acts by complexing the sugar phosphate head group of the peptidoglycan precursor lipid II, thereby inhibiting the transglycosylation reaction of peptidoglycan biosynthesis. 相似文献10.
Svetlana?E?Moskalenko Svetlana?V?Chabelskaya Sergei?G?Inge-Vechtomov Michel?Philippe Galina?A?Zhouravleva
Background
Termination of protein synthesis in eukaryotes involves at least two polypeptide release factors (eRFs) – eRF1 and eRF3. The highly conserved translation termination factor eRF1 in Saccharomyces cerevisiae is encoded by the essential gene SUP45. 相似文献11.
Jens Schneider Petra Peters-Wendisch K Corinna Stansen Susanne Götker Stanislav Maximow Reinhard Krämer Volker F Wendisch 《BMC microbiology》2012,12(1):6
Background
The amino acid-producing Gram-positive Corynebacterium glutamicum is auxotrophic for biotin although biotin ring assembly starting from the precursor pimeloyl-CoA is still functional. It possesses AccBC, the α-subunit of the acyl-carboxylases involved in fatty acid and mycolic acid synthesis, and pyruvate carboxylase as the only biotin-containing proteins. Comparative genome analyses suggested that the putative transport system BioYMN encoded by cg2147, cg2148 and cg2149 might be involved in biotin uptake by C. glutamicum. 相似文献12.
Background
The age of unisexual salamanders of the genus Ambystoma is contentious. Recent and ancient evolutionary histories of unisexual Ambystoma were proposed by a few separate studies that constructed phylogenies using mitochondrial DNA markers (cytochrome b gene vs. non-coding region). In contrast to other studies showing that unisexual Ambystoma represent the most ancient unisexual vertebrates, a recent study by Robertson et al. suggests that this lineage has a very recent origin of less than 25,000 years ago. 相似文献13.
M. Ohnishi A.T. Okatani H. Esaki K. Harada T. Sawada M. Murakami K. Marumo Y. Kato R. Sato K. Shimura N. Hatanaka T. Takahashi 《Journal of applied microbiology》2013,115(1):282-289
Aims
To determine the herd prevalence of Enterobacteriaceae producing CTX‐M‐type extended‐spectrum β‐lactamases (ESBLs) among 381 dairy farms in Japan.Methods and Results
Between 2007 and 2009, we screened 897 faecal samples using BTB lactose agar plates containing cefotaxime (2 μg ml?1). Positive isolates were tested using ESBL confirmatory tests, PCR and sequencing for CTX‐M, AmpC, TEM and SHV. The incidence of Enterobacteriaceae producing CTX‐M‐15 (n = 7), CTX‐M‐2 (n = 12), CTX‐M‐14 (n = 3), CMY‐2 (n = 2) or CTX‐M‐15/2/14 and CMY‐2 (n = 4) in bovine faeces was 28/897 (3·1%) faecal samples. These genes had spread to Escherichia coli (n = 23) and three genera of Enterobacteriaceae (n = 5). Herd prevalence was found to be 20/381 (5·2%) dairy farms. The 23 E. coli isolates showed clonal diversity, as assessed by multilocus sequence typing and pulsed‐field gel electrophoresis. The pandemic E. coli strain ST131 producing CTX‐M‐15 or CTX‐M‐27 was not detected.Conclusions
Three clusters of CTX‐M (CTX‐M‐15, CTX‐M‐2, CTX‐M‐14) had spread among Japanese dairy farms.Significance and Impact of the Study
This is the first report on the prevalence of multidrug‐resistant CTX‐M‐15–producing E. coli among Japanese dairy farms. 相似文献14.
M.J. Torres A. Hidalgo‐García E.J. Bedmar M.J. Delgado 《Journal of applied microbiology》2013,114(6):1772-1781
Aim
In this work, phenotypic analyses of a Ensifer meliloti fixN1 mutant under free‐living and symbiotic conditions have been carried out.Methods and Results
Ensifer meliloti fixN1 mutant showed a defect in growth as well as in TMPD‐dependent oxidase activity when cells were incubated under micro‐oxic conditions. Furthermore, haem c staining analyses of a fixN1 and a fixP1 mutant identified two membrane‐bound c‐type cytochromes of 27 and 32 kDa, present in microaerobically grown cells and in bacteroids, as the FixO and FixP components of the E. meliloti cbb3 oxidase. Under symbiotic conditions, fixN1 mutant showed a clear nitrogen fixation defect in alfalfa plants that were grown in an N‐free nutrient solution during 3 weeks. However, in plants grown for a longer period, fixNOQP1 copy was not indispensable for symbiotic nitrogen fixation.Conclusions
The copy 1 of the fixNOQP operon is involved in E. meliloti respiration and growth under micro‐oxic conditions as well as in the expression of the FixO and FixP components of the cbb3 oxidase present in free‐living microaerobic cultures and in bacteroids. This copy is important for nitrogen fixation during the early steps of the symbiosis.Significance and Impact of the Study
It is the first time that a functional analysis of the E. meliloti copy 1 of the fixNOQP operon is performed. In this work, the cytochromes c that constitute the cbb3 oxidase operating in free‐living micro‐oxic cultures and in bacteroids of E. meliloti have been identified. 相似文献15.
Cheryl-lynn Y Ong Scott A Beatson Makrina Totsika Christiane Forestier Alastair G McEwan Mark A Schembri 《BMC microbiology》2010,10(1):183
Background
Catheter-associated urinary tract infection (CAUTI) is the most common nosocomial infection in the United States and is caused by a range of uropathogens. Biofilm formation by uropathogens that cause CAUTI is often mediated by cell surface structures such as fimbriae. In this study, we characterised the genes encoding type 3 fimbriae from CAUTI strains of Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Citrobacter koseri and Citrobacter freundii. 相似文献16.
Background
Does the C. elegans nervous system contain multi-neuron computational modules that perform stereotypical functions? We attempt to answer this question by searching for recurring multi-neuron inter-connectivity patterns in the C. elegans nervous system's wiring diagram. 相似文献17.
Background
Escherichia coli can respire anaerobically using dimethyl sulfoxide (DMSO) or trimethylamine-N-oxide (TMAO) as the terminal electron acceptor for anaerobic energy generation. Expression of the dmsABC genes that encode the membrane-associated DMSO/TMAO reductase is positively regulated during anaerobic conditions by the Fnr protein and negatively regulated by the NarL protein when nitrate is present. 相似文献18.
19.
Cholesterol‐α‐glucosyltransferase gene is present in most Helicobacter species including gastric non‐Helicobacter pylori helicobacters obtained from Japanese patients
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Masatomo Kawakubo Kazuki Horiuchi Takehisa Matsumoto Jun Nakayama Taiji Akamatsu Tsutomu Katsuyama Hiroyoshi Ota Junji Sagara 《Helicobacter》2018,23(1)
Background
Non‐Helicobacter pylori helicobacters (NHPHs) besides H. pylori infect human stomachs and cause chronic gastritis and mucosa‐associated lymphoid tissue lymphoma. Cholesteryl‐α‐glucosides have been identified as unique glycolipids present in H. pylori and some Helicobacter species. Cholesterol‐α‐glucosyltransferase (αCgT), a key enzyme for the biosynthesis of cholesteryl‐α‐glucosides, plays crucial roles in the pathogenicity of H. pylori. Therefore, it is important to examine αCgTs of NHPHs.Materials and Methods
Six gastric NHPHs were isolated from Japanese patients and maintained in mouse stomachs. The αCgT genes were amplified by PCR and inverse PCR. We retrieved the αCgT genes of other Helicobacter species by BLAST searches in GenBank.Results
αCgT genes were present in most Helicobacter species and in all Japanese isolates examined. However, we could find no candidate gene for αCgT in the whole genome of Helicobacter cinaedi and several enterohepatic species. Phylogenic analysis demonstrated that the αCgT genes of all Japanese isolates show high similarities to that of a zoonotic group of gastric NHPHs including Helicobacter suis, Helicobacter heilmannii, and Helicobacter ailurogastricus. Of 6 Japanese isolates, the αCgT genes of 4 isolates were identical to that of H. suis, and that of another 2 isolates were similar to that of H. heilmannii and H. ailurogastricus.Conclusions
All gastric NHPHs examined showed presence of αCgT genes, indicating that αCgT may be beneficial for these helicobacters to infect human and possibly animal stomachs. Our study indicated that NHPHs could be classified into 2 groups, NHPHs with αCgT genes and NHPHs without αCgT genes. 相似文献20.